Brake pads are designed to absorb heat as they create friction against thebrake rotor. The brake pads ride against either side of the brake rotor and are held in place by the brake caliper that is typically mounted to the spindle or backing plate. Hydraulic pressure is provided by the brake system via a brake master cylinder. When the brake system is activated the brake pads are forced against the brake rotor causing it to slow down, in turn slowing the motion of the car Heat is created and dissipated through the brake pad and rotor. If a bake pad or rotor become overheated it can hinder the brake operation until cooled.
Brake pads are designed to withstand the amount of ,. While the backing plates of all brake pads are made of metal there are several different classifications of the brake composite, for example; organic, semi metallic and ceramic to name a few. The organic pad is used mainly for stock applications, the semi metallic is used for trucks and SUV's while the ceramic pad is used for race and extreme conditions. Each of these pads possess individual wear and usage characteristics, for example; organic pads are the most forgiving pad when it comes to brake rotor wear, and tend to make less brake noise such assqueaking.
Semi metallic pads tend to be more abusive to the rotors but can take more heat before brake fade occurs. Ceramic pads are the hardest pad of the group and will wear out the rotors over the life of the brake pad. Ceramic pads can also be associated with brake pad producing noises like squeaking, grumbling and other undesirablenoises. The advantage of the ceramic pads is the lifespan of the brake pad set is about 25% longer than a regular brake pad. Every brake pad manufacturer has their own mixture of composite material that can vary in cost and quality. This material is bonded or riveted to the metal backing plate that is fitted into the brake caliper.
When servicing or replacing brake pads it is advised to wear a breathing mask over your nose and mouth to avoid inhaling brake dust particles. It is also advisable to wear gloves to avoid skin irritation. These dust particles have been known to cause health problems when exposed to them for an extended amount of time. When replacing brake pad always match the old brake pads to the new brake pads. The backing plate of the brake pad should be identical to the old brake pads, except for the missing brake pad composite material. Some brake pads are fitted with anti rattle clips. These clips are design to allow the brake pads to move freely within the caliper mount.
If these clips are not included with the brake pad set transfer the old clips to the new brake pads set. Do not discard the anti rattle clips this will result in the brake pad having excessive clearance which will create apop or click sound when the brakes are applied. Some brake pad design will include a screamer style of wear indicator. This minimum thickness indicator was created to make a "chirping or screaming noise" when the brakes are in the "idle" position or when the brakes are applied. In an effort to help keep the brake pad in place manufacturers have designed "built in" clips that hold the pad to the inside and outside of the caliper. The inboard pad clip fits inside the caliper piston while the outboard pad clip attaches to the outer part of the caliper. These holder clips hold the brake pads to the brake caliper when it is not bolted to the spindle.
Squeaking or Grumbling Brakes
Brake squeak is one of the most common problems that can occur when the brakes are in operation. The brake squeaking noise is caused by ultra smallvibrations that develop into an audible frequency. There are a number of reasons brakes can produce this noise. The most common cause of brake squeak is cheap or inferior brake pads and rotors. As in most things in life you get what you pay for, and cheap brake components are cheap for a reason. They are made using sub-par material and below average manufacturing techniques.
These brake components tend to wear out more rapidly with below average performance characteristics. There is additional steps you can take to help insure quite brake operation. When installing new brake pads use brake pad shims. These shims act as a shock absorber to dampen brake vibration which will help stop brake squeak. Heat can affect brake pads in a negative way, if the brake pad has over heated it can cause the composite material to become crystallized, when crystallization occurs the brake pad becomes harder.
If a brake pad is hardened it can cause brake squeak. Once the condition has occurred you must replace the brake pads with a new set to repair the problem. When replacing brake pads is advisable to replace or re-machine the brake rotor. The reason for this is because when a brake is used over the life of the brake pad it will develop an un-even surface across the face of the brake rotor. If new brake pads are installed onto a worn brake rotor it can cause irregular brake operation and squeaking. This can cause the brake pedal or steering wheel to pulse when the brakes are in operation.